Apparatus with a self-cleaning electrode for sensing at least one parameter in water
Apparatus ( 2 ) for sensing at least one parameter in water, which apparatus ( 2 ) comprises: (i) at least one electrode based sensor ( 4, 6 ) for sensing at least one parameter in water; and which apparatus ( 2 ) is such that: (ii) the electrode based sensor ( 4, 6 ) has a self-cleaning electrode; (iii) the electrode based sensor ( 4, 6 ) has a reference electrode; (iv) the self-cleaning electrode is stable in water; (v) the apparatus ( 2 ) is configured to operate by liberating chlorine from the water using a first waveform applied to the self-cleaning electrode; (VI) the apparatus ( 2 ) is configured to operate by liberating chlorine and oxygen from the water using a second waveform applied to the self-cleaning electrode; and (VII) the apparatus ( 2 ) is configured to preserve the condition of the reference electrode by periodically regenerating the reference electrode.
1. Apparatus for sensing at least one parameter in water containing compounds of chlorine, which apparatus comprises:
(i) at least one electrode based sensor for sensing at least one parameter in water;
and which apparatus is such that:
(ii) the electrode based sensor has at least one sensing electrode which is also a self-cleaning electrode;
(iii) the electrode based sensor has a reference electrode;
(iv) the self-cleaning electrode is stable in water;
(v) the apparatus includes a single integrated digitally controllable electronic circuit comprising a digital controller and an amplifier; and
(vi) the single integrated digitally controllable electronic circuit:
(a) applies a first waveform to the self-cleaning electrode to liberate chlorine from the water;
(b) applies a second waveform to the self-cleaning electrode to liberate chlorine and oxygen from the water; and
(c) periodically applies a third waveform to the reference electrode to preserve the condition of the reference electrode by periodically regenerating the reference electrode.
2. Apparatus according to claim 1 in which the self-cleaning electrode is a platinum electrode or a palladium electrode.
3. Apparatus according to claim 1 in which the reference electrode is a metal chloride electrode.
4. Apparatus according to claim 3 in which the metal chloride electrode is a silver chloride electrode.
5. Apparatus according to claim 1 in which the electrode based sensor is a conductivity sensor for sensing conductivity in the water.
6. Apparatus according to claim 1 in which the electrode based sensor is an oxygen sensor for sensing dissolved oxygen in the water.
7. Apparatus according to claim 1 in which there is more than one sensor, and in which all of the sensors are on a single substrate.
8. Apparatus according to claim 1 and including a depth sensor for sensing the depth of the water.